ADS-B   Automatic Dependent Surveillance Broadcast

ADS-B is a technology in which airplanes determine their position via satellite navigation and periodically broadcast it in the form of very short messages (squitters), enabling them to be tracked.

The information can be received by air traffic control ground stations to augment surveillance radar. It can also be received by other aircraft to provide situational awareness and allow self-separation.

ADS–B is automatic in that it requires no pilot or external input, as no interrogation signal is needed from the ground. It is dependent surveillance in that it depends on data from the aircraft's navigation system. ADS-B equipped aircraft broadcast their exact position, speed and heading. Those that don't provide positions can be tracked via multilateration (MLAT) when the signal is received by three or more receivers.

Enhanced Surveillance (EHS) includes more details about the aircraft status, navigation intent, and weather at altitude.

A large community of keen enthusiasts and government agencies operate receivers that track ADS-B equipped aircraft worldwide. They share this data with websites that collate and publish it on maps. We operate a number of receiving stations, both stationary and mobile.